Functional dyspepsia (FD) is a very common gastrointestinal (GI) disorder. At present there is no reliable means to diagnose this disease and diagnosis is based on symptoms presented.
Investigators working on FD have identified that many patients having FD have delayed gastric emptying and weak antral motility. Recently, studies have also shown that patients having FD have impaired accommodation of the proximal stomach to meals (Salet et al, Gut, 42:823–829, 1998, Tack et al, Gastroenterology, 115:1346–1352, 1998). Using barostat techniques and ultrasonography it has been shown that the reservoir function of the proximal stomach is abnormal in a significant proportion of FD patients. The reflex regulating the reservoir function of the stomach is called adaptive accommodation and it is thought to be mediated by both intrinsic and extrinsic (vagal) neuronal pathways. It has been suggested that abnormal vagal activity might be the reason for the impaired accommodation of the stomach in FD patients. The impaired gastric accommodation might also cause the increase in visceral sensitivity and symptoms.
There are a few reports in the literature of animal models for the use in studying pressure-volume handling in conscious animals. Bueno et al disclosed a rat model to study gastric sensitivity and measured the maximal volume at a pressure of 20 mmHg and the visceromotor response related to maximal volume (Neurogastroenterology & Motility, 10(2):157–63, 1998). Paterson et al conducted studies in dogs using barostat technique and examined the effect of different pharmacological substances on the maximum volume of the stomach (Neurogastroenterology & Motility, 12(4):301–6, 2000). No studies have been reported where the physico-mechanical properties of the stomach have been studied in detail in response to distension.